light a fire under


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Related to light a fire under: alight

light a fire under somebody

to make someone work better or harder It's time you lit a fire under those guys or they'll never finish painting the house.
See also: fire, light

light a fire under somebody

  (mainly American)
to make someone work better or harder It's time you lit a fire under those guys or they'll never finish painting the house.
See also: fire, light

light a fire under

Also, build a fire under. Urge or goad to action, as in If we don't light a fire under that committee, they'll never do any work. This hyperbolic colloquialism uses light in the sense of "ignite," a usage dating from the mid-1100s.
See also: fire, light

light a fire under

To urge or move to action.
See also: fire, light